Fracture and Crack Probability in Teeth Based on Degree of Structural Loss and Type of Restoration

BACKGROUND: The reported frequency of dental fractures and cracks depending on the degree of tooth destruction and type of restoration does not reflect the probability of these complications under specific clinical conditions. Therefore, statistical modeling of tooth fracture and crack probability under various conditions of dental integrity is highly relevant. AIM: The study aimed to assess the detection rate and probability of fractured and cracked teeth as related to the extent of structural loss and the method for restoration. METHODS: In 2024, the Clinical Center of Dentistry, Federal Medical and Biological Agency of Russia, conducted an observational study evaluating the frequency and clinical context of fractured and cracked teeth. Annual reports on treatment volume and structure for dental caries, its complications, and hard tissue restorations were also analyzed. Fracture probability was calculated using a formula incorporating the specific condition under which a fracture or crack was identified, the number of such cases, and the number of corresponding restorative procedures performed within the same time frame. RESULTS: The detection rate of fractured and cracked teeth was 8.9%, predominantly occurring within 5 years after treatment. The calculated five-year complication probability ranged from 7.8% in vital teeth to 32.8% in devitalized teeth. The highest probabilities were associated with unrestored cavity occupying more than half of the occlusal surface (44.5%) and teeth reinforced with metal posts (52.9%). CONCLUSION: The five-year fracture and crack probability estimates indicate a marked predisposing effect of the following conditions: devitalization; use of the tooth as an abutment for a removable partial denture; an unrestored cavity occupying more than half of the occlusal surface; and intraradicular reinforcement with a metallic post.